1. The emotion one gets when they begin to feel depressed for depressions sake, especially whilst they are happy.
Ex: fake depression
2. The feeling you get from listening to your favorite songs, which are about being depressed.
3. The happy way listening to Jawbreaker records for hours makes you feel, melancholy.
4. Happy and sad at the same time.
5. Faking happiness when you're really sad.

I had a really great day, but listening to my emo music made me mellowcholy.